Interferometric methods have been used to monitor tissue surface movements of nanometer dimention in a nsec time scale. This has been used to study the onset of laser ablation. The results have been published in a series of publication published recently. The improved technique has allowed careful monitoring of laser-induced cavitation phenomenon in water with a temporal resolution of a few nanoseconds. This technique has also been applied to "soft" tissue (meniscus) and it has been shown that cavitation occurs within meniscus. This technique is currently being used to determine the cavitation threshold (tensile strength) of water and saline.